package com.simplenix.nicasio.sys;

import com.simplenix.nicasio.def.Module;
import com.simplenix.nicasio.misc.FileUtil;
import java.io.IOException;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.List;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 *
 * @author fronald
 */
public class SecurityFilter implements Filter {

	// The filter configuration object we are associated with.  If
	// this value is null, this filter instance is not currently
	// configured.
	private FilterConfig filterConfig = null;

	public SecurityFilter() {
	}

	/**
	 *
	 * @param request The servlet request we are processing
	 * @param response The servlet response we are creating
	 * @param chain The filter chain we are processing
	 *
	 * @exception IOException if an input/output error occurs
	 * @exception ServletException if a servlet error occurs
	 */
	public void doFilter(ServletRequest request, ServletResponse response,
			FilterChain chain)
			throws IOException, ServletException {

		try {
			List<Module> modules = SystemDef.getInstance().getModules().getModulesList();
			for (Module module : modules) {
				List<String> classes = FileUtil.getClassList(module.getBasePackage() + ".requestfilters");
				for (String className : classes) {
					RequestFilter r = (RequestFilter) Class.forName(className).newInstance();
					r.doFilter((HttpServletRequest) request, (HttpServletResponse) response, chain);
				}
			}
		} catch (Exception e) {
			throw new ServletException(e);
		}

		Throwable problem = null;
		try {
			chain.doFilter(request, response);
		} catch (Throwable t) {
			problem = t;
			t.printStackTrace();
		}

		if (problem != null) {
			if (problem instanceof ServletException) {
				throw (ServletException) problem;
			}
			if (problem instanceof IOException) {
				throw (IOException) problem;
			}
			sendProcessingError(problem, response);
		}
	}

	/**
	 * Return the filter configuration object for this filter.
	 */
	public FilterConfig getFilterConfig() {
		return (this.filterConfig);
	}

	/**
	 * Set the filter configuration object for this filter.
	 *
	 * @param filterConfig The filter configuration object
	 */
	public void setFilterConfig(FilterConfig filterConfig) {
		this.filterConfig = filterConfig;
	}

	/**
	 * Destroy method for this filter
	 */
	public void destroy() {
	}

	/**
	 * Init method for this filter
	 */
	public void init(FilterConfig filterConfig) {
		this.filterConfig = filterConfig;
		if (filterConfig != null) {
		}
	}

	/**
	 * Return a String representation of this object.
	 */
	@Override
	public String toString() {
		if (filterConfig == null) {
			return ("SecurityFilter()");
		}
		StringBuffer sb = new StringBuffer("SecurityFilter(");
		sb.append(filterConfig);
		sb.append(")");
		return (sb.toString());
	}

	private void sendProcessingError(Throwable t, ServletResponse response) {
		String stackTrace = getStackTrace(t);

		if (stackTrace != null && !stackTrace.equals("")) {
			try {
				response.setContentType("text/html");
				PrintStream ps = new PrintStream(response.getOutputStream());
				PrintWriter pw = new PrintWriter(ps);
				pw.print("<html>\n<head>\n<title>Error</title>\n</head>\n<body>\n"); //NOI18N

				// PENDING! Localize this for next official release
				pw.print("<h1>The resource did not process correctly</h1>\n<pre>\n");
				pw.print(stackTrace);
				pw.print("</pre></body>\n</html>"); //NOI18N
				pw.close();
				ps.close();
				response.getOutputStream().close();
			} catch (Exception ex) {
			}
		} else {
			try {
				PrintStream ps = new PrintStream(response.getOutputStream());
				t.printStackTrace(ps);
				ps.close();
				response.getOutputStream().close();
			} catch (Exception ex) {
			}
		}
	}

	public static String getStackTrace(Throwable t) {
		String stackTrace = null;
		try {
			StringWriter sw = new StringWriter();
			PrintWriter pw = new PrintWriter(sw);
			t.printStackTrace(pw);
			pw.close();
			sw.close();
			stackTrace = sw.getBuffer().toString();
		} catch (Exception ex) {
		}
		return stackTrace;
	}

	public void log(String msg) {
		filterConfig.getServletContext().log(msg);
	}

}
